1. Field of the Invention
The present invention relates to a multifunctional portable telephone which enables use of functions which do not require transmission and reception of radio waves, such as creating e-mails, managing personal information and playing games, and in particular to a multifunctional portable telephone with a transmission and reception stop control function.
2. Description of the Related Art
In recent years, mobile communications as represented by cellular car telephones or portable telephones have become widespread, and it is thought that multifunctional portable telephones with PDA (Personal digital Assistants) function, etc. will also become increasingly popular.
Further, current portable telephones which are provided with a screen display device such as a liquid crystal panel and an input device by key-inputting etc., have functions as a telephone, that is, transmission and reception of radio waves, and in addition they are much more likely to become multifunctional by having functions for exchanging e-mails and for enjoying game-playing.
Hereinafter, the expression “telephone function” is described as a function of a telephone that involves transmission and reception of radio waves, and the expression “non-telephone function” is described as a function that does not involve the transmission and reception of radio waves, such as e-mail creation and game-playing.
When an incoming call is received while playing games downloaded onto such a multifunctional portable telephone or while composing a text message for e-mail, strong electromagnetic waves for registering location, etc. may be emitted.
Usually, when a portable telephone is turned on, the portable telephone performs communications at designated intervals in order to expressly inform a user of the state of communication with a base station, and radio waves are transmitted and received regardless of whether or not transmission for conversation is being carried out by telephone. Because radio waves may affect precision machines, areas or situations are designated in which the use of portable telephones is prohibited or restricted. That includes, needless to say, in hospitals and trains. One example is that the use of portable telephones on a crowded train might cause a malfunction in the cardiac pacemaker of a nearby passenger. Further, although this example does not show an adverse effect of electromagnetic waves, an incoming call sound at a public performance, etc. may become an annoyance to neighbors.
Due to these problems, in an area, such as in hospitals or on aircraft, where communication with portable telephones is prohibited, a practice of turning off portable telephones is adopted. However, there is the problem that turning-off makes it impossible to use all the functions of a portable telephone. Namely, even non-telephone functions that are not associated with emission of electromagnetic waves, such as viewing information, for example telephone numbers, registered in a portable telephone become unavailable. For example, because a portable telephone is turned off in a hospital, the user of the portable telephone cannot view telephone number information registered in the portable telephone in order to make a call by a public telephone.
As a method to solve these problems, for example, Japanese Patent Application Laid-Open (kokai) No. 11-284723 discloses a portable telephone which is provided with a transmission and reception stop and start button for stopping or restarting only transmission and reception functions that emit strong electromagnetic waves. In addition, there is disclosed a device which stops a function of radio wave transmission and reception in a radio communication prohibited area in Japanese Patent Applications Laid-Open (kokai) Nos. 11-225378 and 11-340901. Further, Japanese Patent Application Laid-Open (kokai) No. 10-304443 discloses a device which automatically turns off power supply in a radio communication prohibited area.
FIG. 10 is a block diagram illustrating the structure of a conventional multifunctional portable telephone. Referring to FIG. 10, the multifunctional portable telephone is composed of an antenna 1 for performing radio communication; a telephone function control unit 2 for controlling telephone functions as a whole; a non-telephone function control unit 3 for controlling non-telephone functions; a system control unit 4 for controlling the entire device; an input unit 5 comprising functional keys for inputting information into the portable telephone; and a display unit 6 comprising, for example, an LCD for displaying personal information or states of the system.
The telephone function control unit 2 is a processing circuit for realizing communications. It is composed of a microphone, a speaker, a base band section, a voice codec section, an RF control section, and the like. The RF control section converts a wave signal to an electric signal by use of the antenna 1. The operational state of the telephone function control unit 2 means the state of transmission and reception of radio waves.
The input unit 5 is composed of dial keys, a power key, and the like. Each of them is operated manually, and the input unit has a function of transferring the contents inputted through those manual operations to the system control unit 4 as information.
On the display unit 6, numbers inputted through the dial keys, various image planes for non-telephone functions, an icon indicating the operational state of the telephone function, or the like are displayed.
Such a structure enables the user to turn off only the telephone function control unit 2, even when the non-telephone control unit 3 is operational. This is done by inputting specific information through the input unit 5 when the power key is operated and the portable telephone is itself turned on. The above-mentioned structure and control allows radio wave output to be stopped, and therefore non-telephone functions can be utilized even in the areas or in the situations mentioned above. At the same time, the telephone function control unit 2 is turned off and efforts to reduce power consumption can be made.
Further, it has been proposed to provide a function for informing the portable telephone user of the operational state of the telephone function by a method of displaying an icon etc. on the display unit 6.
These conventional multifunctional portable telephones, however, have the following drawbacks.
With respect to the devices disclosed in Japanese Patent Applications Laid-Open (kokai) Nos. 11-284723, 11-225378, and 11-340901, when the portable telephones are turned on, transmission and reception can only be turned to a stop state by using the transmission and reception stop and start button and it is only possible to revert to an active state by pressing the same button. However, when those portable telephones are turned off, functions other than functions relating to electromagnetic wave emission cannot directly be made available. In other words, on aircraft or in hospitals, a user has to turn off both the transmission and reception stop/release button and the power button of the portable telephone. This is inconvenient. In addition, during the stop state of transmission and reception, even operations relating to only reception such as cell search are in a stop state and thus a problem arises, that is, it takes some time before communication is available when transmission and reception is resumed.
On the other hand, with respect to the device disclosed in Japan Patent Application Laid-Open (kokai) No. 10-304443, 2 transmitters are provided at an entrance of a radio communication prohibited area. A reception unit of a portable terminal judges only whether or not transmission frequencies of the 2 transmitters are received and then, based on the judgment, power supply to a transmission unit is changed over. Because of this, such function is effective only in a radio communication prohibited area wherein 2 transmitters are provided in advance. It have been very difficult to realize the above in other radio communication prohibited areas or transportation facilities such as trains. Further, there is no disclosure on use of functions such as viewing telephone number lists in a radio communication prohibited area.
Furthermore, in the case of the above mentioned portable telephone, when a user decides that he is in an area or in a situation mentioned above where use of a portable telephone is prohibited or restricted, the user sets the portable telephone to stop its telephone function by his own operation. In addition, when the user moves to an area or a situation other than the above, the user manually resets the portable telephone so that the telephone function is usable as usual. Moreover, in order to prevent the user from forgetting this resetting operation, the portable telephone has a function to give a notification to the user of the portable telephone.
Although it is easily recognized, even from the viewpoint of a third person, that a portable telephone user is in an area or in a situation where use of the portable telephone is prohibited or restricted, a stop state of the telephone function of the portable telephone in use, that is a state wherein radio waves are not transmitted or received, can be recognized only by the user of the portable telephone.
In this case, even though the user of the portable telephone sets the portable telephone to stop its telephone function, a third person cannot recognize that the portable telephone is in the stop state. Therefore, there is considered a case wherein, when the user is overly concerned about being misunderstood by the third person, he does not use the portable telephone after all.
Further, the user of the above portable telephone has to manually set the telephone function into operation or stop. On trains or the like, the user may forget that the portable telephone is turned on. Another case may be considered wherein, depending on the user's sense of social responsibility, he does not use the above function even though it is provided on his portable telephone. In this case, when a third person using medical equipment etc. is in the vicinity, that person is disturbed considerably.